1. Field of the Invention
The present invention relates to an optical recording medium on which predetermined command code is recorded in a predetermined region in which contents are stored, and an apparatus and method to play the optical recording medium and which executes a predetermined command when the contents are played so that the predetermined command is moved into contents at a predetermined portion of a screen on which the contents are displayed.
2. Description of the Related Art
In general, a digital versatile disc (DVD) is the same size as a compact disc (CD) having a diameter of 12 cm and a thickness of 1.2 mm but is capable of storing 7 times as much data as a CD. A CD has a capacity to hold data sufficient to play for 74 minutes (i.e., to play a capacity of 688 megabytes). A DVD has a capacity of 4.7-17 gigabytes depending on whether the DVD is single sided or double sided and is formed of a single layer or multiple layers. Since the DVD has a large capacity, the DVD can provide better video than the CD. Further, the DVD need not use a moving picture experts group (MPEG)-1 compression method, which places more weight on high compression than on picture quality, but instead can use an MPEG-2 compression method, which places more weight on picture quality.
By providing audio and subtitles and by assigning a space in which information including all kinds of set-up menus are stored, many functions can be provided. These functions can include an interactive (conversation-type) progress function to reproduce contents according to a user's selection, a multilingual subtitle processing function to display a maximum of 32 languages, a multilingual speech processing function to provide sound tracks in a maximum of 8 languages, a digital surround function that is provided through six speakers (e.g., front-right, front-left, back-right, back-left, central, middle and low frequency speakers), a multi-story function in which a user selects from many preset stories in the case of a movie, a multi-angle function in which a scene that is filmed in various angles is provided and a viewer can select a desired angle and can view a scene from that angle, and a viewing-restriction function to restrict viewing by grading each scene.
Among the set-up menus of the DVD, there is a sub-title menu to set the language and the subtitles. The sub-title menu is useful and is often used to allow a user to enjoy various discs in different languages. However, a conventional DVD includes only a subtitle processing function in a selected language, and thus, a learning function cannot be enhanced.